Identification and expression analysis of TCP family members in tobacco (Nicotiana tabacum L.) / 生物工程学报

TCP family as plant specific transcription factor, plays an important role in different aspects of plant development. In order to screen TCP family members in tobacco, the homologous sequences of tobacco and Arabidopsis TCP family were identified by genome-wide homologous alignment. The physicochemical properties, phylogenetic relationships and cis-acting elements were analyzed by bioinformatics. The homologous genes of AtTCP3/AtTCP4 were screened, and RT-qPCR was used to detect the changes of gene expression upon 20% PEG6000 treatment. The results show that tobacco contains 63 TCP family members. Their amino acid sequence length ranged from 89 aa to 596 aa, and their protein hydropathicity grand average of hydropathicity (GRAVY) ranged from -1.147 to 0.125. The isoelectric point (pI) ranges from 4.42 to 9.94, the number of introns is 0 to 3, and the subcellular location is all located in the nucleus. The results of conserved domain and phylogenetic relationship analysis showed that the tobacco TCP family can be divided into PCF, CIN and CYC/TB1 subfamilies, and each subfamily has a stable sequence. The results of cis-acting elements in gene promoter region showed that TCP family genes contain low docile acting elements (LTR) and a variety of stress and metabolic regulation related elements (MYB, MYC). Analysis of gene expression patterns showed that AtTCP3/AtTCP4 homologous genes (NtTCP6, NtTCP28, NtTCP30, NtTCP33, NtTCP42, NtTCP57, NtTCP63) accounted for 20% PEG6000 treatment significantly up-regulated/down-regulated expression, and NtTCP30 and NtTCP57 genes were selected as candidate genes in response to drought. The results of this study analyzed the TCP family in the tobacco genome and provided candidate genes for the study of drought-resistance gene function and variety breeding in tobacco.

Effect of seasonality on the leaf phenology and physiology of Byrsonima species (Malpighiaceae)

Introduction: Defined seasonality in savanna species can stimulate physiological responses that maximize photosynthetic metabolism and productivity. However, those physiological responses are also linked to the phenological status of the whole plant, including leaf phenophases. Objective: To study how physiological traits influence phenophase timing among congeneric and co-occurring savanna species. Methods: We evaluated the leaf phenology and physiological traits of populations of Byrsonima intermedia, B. coccolobifolia, and B. verbascifolia. Physiological measurements were performed at the onset of the dry and rainy seasons and again late in the season. Results: B. intermedia and B. coccolobifolia were classified as brevideciduous and B. verbascifolia as evergreen. The maximum quantum yield for B. intermedia and B. coccolobifolia were lowest during the dry season. At the onset of the dry period, the highest chloroplastidic pigment levels were observed, which decreased as the season advanced, total chlorophyll/carotenoid ratios were lowest, and carotenoid contents were highest. We detected low starch content values at the start of the rainy season, coinciding with the resumption of plant growth. Two months into this season, the leaves were at their peak structural and functional maturity, with high water-soluble polysaccharide values and photosynthetic rates, and were storing large amounts of starch. Conclusions: Physiological and leaf phenological strategies of the Byrsonima species were related to drought resistance and acclimatization to the seasonality of savanna water resources. The oscillations of the parameters quantified during the year indicated a strong relationship with water seasonality and with the phenological status of the leaves.

Introducción: La marcada estacionalidad en las especies de sabana puede estimular respuestas fisiológicas que maximicen el metabolismo fotosintético y la productividad. Sin embargo, esas respuestas fisiológicas están vinculadas al estado fenológico de toda la planta, incluidas las fenofases de las hojas. Objetivo: Estudiar cómo los rasgos fisiológicos influyen en el tiempo de la fenofase entre especies de sabana congenéricas y concurrentes. Métodos: Evaluamos la fenología y características fisiológicas de poblaciones de Byrsonima intermedia, B. coccolobifolia y B. verbascifolia. Las mediciones fisiológicas se realizaron al inicio de la estación seca y lluviosa, y de nuevo al final de la estación. Resultados: B. intermedia y B. coccolobifolia se clasificaron como brevicaducifolias y B. verbascifolia como perennifolias. El rendimiento cuántico máximo para B. intermedia y B. coccolobifolia fueron más bajos durante la época seca. Al inicio del período seco, se observaron niveles de pigmentos cloroplastídicos más altos, aunque los niveles de clorofila disminuyeron a medida que avanzaba la estación seca, las proporciones clorofila/carotenoides totales fueron más bajas y los contenidos de carotenoides más altos. Detectamos valores bajos de contenido de almidón al inicio de la época lluviosa, que coincide con la reanudación del crecimiento de la planta. A dos meses de esta época, las hojas estaban en su máxima madurez estructural y funcional, con altos valores de polisacáridos solubles en agua y tasas fotosintéticas, y almacenaban grandes cantidades de almidón. Conclusiones: Las estrategias fisiológicas y fenológicas de las hojas de las especies de Byrsonima estaban relacionadas con la resistencia a la sequía y la aclimatación a la estacionalidad de los recursos hídricos de la sabana. Las oscilaciones de los parámetros cuantificados durante el año indicaron una fuerte relación con la estacionalidad hídrica y con los estados fenológicos de las hojas.

Growth and functional leaf traits of coppice regrowth of Bertholletia excelsa during an El Niño event in the central Amazon / Crescimento e características funcionais foliares de rebrotas de Bertholletia excelsa durante um evento de El Niño na Amazônia Central

The most severe drought of this century in the Amazon rainforest, which was caused by El Niño, occurred from 2015 to 2016. With a focus on the ecophysiology of the regrowth of the Brazil nut tree, Bertholletia excelsa, it was investigated how the progression of the drought of 2015-2016 affected the physiological traits of the coppice regrowth of B. excelsa. The experiment was carried out in a ten-year-old plantation of Brazil nut trees, which had been subjected to thinning and coppice regrowth two years earlier. In the sprouts grown on the stumps of cut trees, the following treatments were applied: (T1) thinning to one sprout per stump; (T2) thinning to two sprouts per stump, and (T3) maintenance of three sprouts per stump. Thinning treatments did not alter the growth and ecophysiological traits of the Brazil nut tree sprouts, though the phosphorus content of the leaves was higher in T1. However, the progression of the drought in 2015-2016 negatively affected the growth (height) and gas exchange of sprouts of all treatments. In addition, an increase of around 37% was observed in the intrinsic wateruse efficiency. Concerning photochemical performance, no alterations were observed. Therefore, drought stress promoted a negative effect on sprout growth and affected traits related to the photosynthesis of the B. excelsa sprouts independently of the number of sprouts per stump.(AU)

A seca mais severa deste século na floresta amazônica, causada por El Niño, ocorreu de 2015 a 2016. Com foco na ecofisiologia da rebrota da castanheira da Amazônia, foi investigado como a progressão da seca de 2015-2016 afetou as características fisiológicas das rebrotas de uma talhadia de B. excelsa. O experimento foi realizado em uma plantação de castanheiras com dez anos, a qual havia sido submetida a um desbaste e rebrota de talhadia dois anos antes. Nas rebrotas crescidas sobre os tocos das árvores cortadas foram aplicados os seguintes tratamentos: (T1) desbrota para manter um broto por cepa; (T2) desbrota para manter dois brotos por cepa; e (T3) manutenção de três brotos por cepa. Os tratamentos de desbrota não alteraram o crescimento e as características ecofisiológicas dos brotos da castanheira, exceto para o teor foliar de fósforo, que foi maior em T1. Porém, a progressão da seca em 2015-2016 afetou negativamente o crescimento em altura e as trocas gasosas dos brotos de todos os tratamentos. Além disso, foi observado um aumento de cerca de 37% na eficiência intrínseca do uso da água. Quanto ao desempenho fotoquímico, não foram observadas alterações. Portanto, o estresse hídrico promoveu efeito negativo no crescimento da brotação e afetou características relacionadas à fotossíntese das brotações de B. excelsa, independentemente do número de brotações por cepa.(AU)

A comprehensive overview of miRNA targeting drought stress resistance in plants / Uma visão geral abrangente do miRNA visando a resistência ao estresse hídrico em plantas

Abstract MicroRNAs (miRNAs) are essential nonprotein-coding genes. In a range of organisms, miRNAs has been reported to play an essential role in regulating gene expressions at post-transcriptional level. They participate in most of the stress responsive processes in plants. Drought is an ultimate abiotic stress that affects the crop production. Therefore understanding drought stress responses are essential to improve the production of agricultural crops. Throughout evolution, plants have developed their own defense systems to cope with the adversities of environmental stresses. Among defensive mechanisms include the regulations of gene expression by miRNAs. Drought stress regulates the expression of some of the functionally conserved miRNAs in different plants. The given properties of miRNAs provide an insight to genetic alterations and enhancing drought resistance in cereal crops. The current review gives a summary to regulatory mechanisms in plants as well as miRNAs response to drought stresses in cereal crops. Some possible approaches and guidelines for the exploitation of drought stress miRNA responses to improve cereal crops are also described.

Resumo MicroRNAs (miRNAs) são genes essenciais não codificadores de proteínas. Em uma variedade de organismos, foi relatado que miRNAs desempenham papel essencial na regulação da expressão gênica em nível pós-transcricional. Eles participam da maioria dos processos responsivos ao estresse nas plantas. A seca é um estresse abiótico final que afeta a produção agrícola. Portanto, compreender as respostas ao estresse da seca é essencial para melhorar a produção de safras agrícolas. Ao longo da evolução, as plantas desenvolveram seus próprios sistemas de defesa para lidar com as adversidades do estresse ambiental. Entre os mecanismos de defesa está a regulação da expressão gênica por miRNAs. O estresse hídrico regula a expressão de alguns dos miRNAs funcionalmente conservados em diferentes plantas. As propriedades dadas dos miRNAs fornecem uma visão das alterações genéticas e aumentam a resistência à seca nas safras de cereais. A revisão atual apresenta um resumo dos mecanismos regulatórios nas plantas, bem como a resposta dos miRNAs ao estresse hídrico nas plantações de cereais. Algumas abordagens e diretrizes possíveis para a exploração das respostas do miRNA ao estresse da seca para melhorar as safras de cereais também são descritas.

Regulon: An overview of plant abiotic stress transcriptional regulatory system and role in transgenic plants / Regulon: Uma visão geral do sistema regulador da transcrição do estresse abiótico em plantas e papel nas plantas transgênica

Abstract Population growth is increasing rapidly around the world, in these consequences we need to produce more foods to full fill the demand of increased population. The world is facing global warming due to urbanizations and industrialization and in this concerns plants exposed continuously to abiotic stresses which is a major cause of crop hammering every year. Abiotic stresses consist of Drought, Salt, Heat, Cold, Oxidative and Metal toxicity which damage the crop yield continuously. Drought and salinity stress severally affected in similar manner to plant and the leading cause of reduction in crop yield. Plants respond to various stimuli under abiotic or biotic stress condition and express certain genes either structural or regulatory genes which maintain the plant integrity. The regulatory genes primarily the transcription factors that exert their activity by binding to certain cis DNA elements and consequently either up regulated or down regulate to target expression. These transcription factors are known as masters regulators because its single transcript regulate more than one gene, in this context the regulon word is fascinating more in compass of transcription factors. Progress has been made to better understand about effect of regulons (AREB/ABF, DREB, MYB, and NAC) under abiotic stresses and a number of regulons reported for stress responsive and used as a better transgenic tool of Arabidopsis and Rice.

Resumo O crescimento populacional está aumentando rapidamente em todo o mundo, e para combater suas consequências precisamos produzir mais alimentos para suprir a demanda do aumento populacional. O mundo está enfrentando o aquecimento global devido à urbanização e industrialização e, nesse caso, plantas expostas continuamente a estresses abióticos, que é uma das principais causas do martelamento das safras todos os anos. Estresses abióticos consistem em seca, sal, calor, frio, oxidação e toxicidade de metais que prejudicam o rendimento da colheita continuamente. A seca e o estresse salino são afetados de maneira diversa pela planta e são a principal causa de redução da produtividade das culturas. As plantas respondem a vários estímulos sob condições de estresse abiótico ou biótico e expressam certos genes estruturais ou regulatórios que mantêm a integridade da planta. Os genes reguladores são principalmente os fatores de transcrição que exercem sua atividade ligando-se a certos elementos cis do DNA e, consequentemente, são regulados para cima ou para baixo para a expressão alvo. Esses fatores de transcrição são conhecidos como reguladores mestres porque sua única transcrição regula mais de um gene; nesse contexto, a palavra regulon é mais fascinante no âmbito dos fatores de transcrição. Progresso foi feito para entender melhor sobre o efeito dos regulons (AREB / ABF, DREB, MYB e NAC) sob estresses abióticos e uma série de regulons relatados como responsivos ao estresse e usados ​​como uma melhor ferramenta transgênica de Arabidopsis e Rice.

Epidemiological research progress on association of drought with mortality / 环境与职业医学

Drought is expected to be more severe and frequent due to climate change. Drought exerts not only extensive impacts on economy and environment, but also direct or indirect impacts on human health. This review systematically collected studies exploring the association between drought and human mortality, and summarized the associations between drought and all-cause mortality, chronic non-communicable disease mortality, communicable disease mortality, and injury mortality. The results revealed that drought was significantly associated with human mortality, leading to an elevated mortality risk of cardiovascular diseases, respiratory diseases, cancers, diarrhea, and injuries; serious drought increased much more mortality risk than mild drought; males in rural areas, the elderly, and children were vulnerable populations to drought. However, in-depth studies on the association of drought with human mortality are limited, which calls for related studies in the future. This review summarized the current research status and existing problems in drought and population death, and pointed out the future research direction, which can provide reference for future related research.

Genetic resources and precise gene editing for targeted improvement of barley abiotic stress tolerance / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Abiotic stresses, predominately drought, heat, salinity, cold, and waterlogging, adversely affect cereal crops. They limit barley production worldwide and cause huge economic losses. In barley, functional genes under various stresses have been identified over the years and genetic improvement to stress tolerance has taken a new turn with the introduction of modern gene-editing platforms. In particular, clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) is a robust and versatile tool for precise mutation creation and trait improvement. In this review, we highlight the stress-affected regions and the corresponding economic losses among the main barley producers. We collate about 150 key genes associated with stress tolerance and combine them into a single physical map for potential breeding practices. We also overview the applications of precise base editing, prime editing, and multiplexing technologies for targeted trait modification, and discuss current challenges including high-throughput mutant genotyping and genotype dependency in genetic transformation to promote commercial breeding. The listed genes counteract key stresses such as drought, salinity, and nutrient deficiency, and the potential application of the respective gene-editing technologies will provide insight into barley improvement for climate resilience.

CeO / 中国生物化学与分子生物学报

Drought is a common limiting factor affecting rice yield and quality. Cerium oxide nanoparticles(nanoceria) have been widely reported to improve crop stress tolerance. However, the effects and mechanisms of nanoceria on rice drought tolerance are still unknown. The aim of this study is to investigate whether nanoceria can improve rice drought tolerance by modulating reactive oxygen species(ROS) homeostasis and nitric oxide(NO) levels. Our results showed that compared with no-nanoparticle treatment, nanoceria significantly increased the fresh weight of rice seedlings under drought stress(19%, P < 0. 05). Also, under drought stress, the ROS level of rice leaves treated with nanoceria was significantly lower(82%, P < 0. 05) than leaves treated with buffer. The leaf NO level after nanoceria treatment, however, is significantly higher(46%, P < 0. 05) than that with no-nanoparticle treatment under drought stress. Moreover, compared with control plants, nanoceria maintained better membrane integrity in rice leaf cells under drought stress, showing a 70% decrease(P < 0. 05) in dead leaf cells. This study explores the mechanisms underlying nanoceria’s improved rice drought tolerance by affecting ROS and NO levels, which not only further enriches our knowledge about the interaction between nanoparticles and crops under abiotic stress but also gives more support on the sustainable development of nano-enabled agriculture.

Biological Mechanism of Drought Improving Quality of Rhizoma Atractylodis Chinensis / 中国实验方剂学杂志

ObjectiveTo explore the biological mechanism of drought improving the quality of Rhizoma Atractylodis Chinensis and establish a new method for the production of high-quality medicinal materials. MethodThe fresh roots of Atractylodes chinensis were soaked in 0 （control）， 5%， 10%， and 20% PEG-6000 solutions. The changes in reactive oxygen species （ROS） level， antioxidant enzyme activity， activities of key enzymes in primary metabolism and secondary metabolism， and content of secondary metabolites were compared. ResultCompared with the control group， the treatment with 20% PEG for 2 days elevated the levels of superoxide anion radicals （O2-·）， hydrogen peroxide （H2O2）， and malondialdehyde （MDA） by 172.5%， 56.9%， and 14.7%， respectively. The treatment did not change the activity of superoxide dismutase （SOD）， reduced the peroxidase （POD） activity， and increased the catalase （CAT） activity by 10.8%. It increased the activities of 3-hydroxy-3-methylglutaryl-CoA reductase （HMGR）， phosphoenolpyruvate carboxylase （PEPC）， and acetyl-CoA carboxylase （ACC） by 49.9%， 12.1%， and 19.0%， respectively. Furthermore， the content of atractylodin， β-eudesmol， atractylone， and atractylenolide Ⅱ was increased by 51.0%， 36.9%， 47.1%， and 91.5%， respectively. The simulated drought stress can cause the burst of ROS in the fresh roots of A. chinensis， induce the physiological state of plants under drought， change the antioxidant system， and promote the massive synthesis of secondary metabolites in a short time. ConclusionPEG-6000-simulated drought stress can greatly improve the quality of A. chinensis in cultivation.

Variation and interaction mechanism between active components in Rheum officinale and rhizosphere soil microorganisms under drought stress / 中国中药杂志

To explore the changes and the reaction mechanisms between soil microecological environment and the content of secon-dary metabolites of plants under water deficit, this study carried out a pot experiment on the 3-leaf stage seedlings of Rheum officinale to analyze their response mechanism under different drought gradients(normal water supply, mild, moderate, and severe drought). The results indicated that the content of flavonoids, phenols, terpenoids, and alkaloids in the root of R. officinale varied greatly under drought stresses. Under mild drought stress, the content of substances mentioned above was comparatively high, and the content of rutin, emodin, gallic acid, and(+)-catechin hydrate in the root significantly increased. The content of rutin, emodin, and gallic acid under severe drought stress was significantly lower than that under normal water supply. The number of species, Shannon diversity index, richness index, and Simpson index of bacteria in the rhizosphere soil were significantly higher than those in blank soil, and the number of microbial species and richness index decreased significantly with the aggravation of drought stresses. In the context of water deficit, Cyanophyta, Firmicutes, Actinobacteria, Chloroflexi, Gemmatimonadetes, Streptomyces, and Actinomyces were the dominant bacteria in the rhizosphere of R. officinale. The relative content of rutin and emodin in the root of R. officinale was positively correlated with the relative abundance of Cyanophyta and Firmicutes, and the relative content of(+)-catechin hydrate and(-)-epicatechin gallate was positively correlated with the relative abundance of Bacteroidetes and Firmicutes. In conclusion, appropriate drought stress can increase the content of secondary metabolites of R. officinale from physiological induction and the increase in the association with beneficial microbe.

Soybean GmGolS2-2 improves drought resistance of transgenic tobacco / 生物工程学报

Galactinol synthase (GolS) genes play important roles in plant response to abiotic stress. In this research, the plant expression vector of soybean GmGolS2-2 gene was constructed and transformed into tobacco to study the drought tolerance of transgenic tobacco. A GmGolS2-2 gene with 975 bp coding sequence was cloned from soybean leaves by reverse transcription-polymerase chain reaction (RT-PCR). GmGolS2-2 was linked to the plant expression vector pRI101 by restriction enzyme sites Nde Ⅰ and EcoR Ⅰ, and transformed into tobacco by leaf disc method. Genomic DNA PCR and real-time PCR showed that three GmGolS2-2 transgenic tobacco plants were obtained. The growth status of GmGolS2-2 transgenic tobacco under drought stress was better than that of wild-type tobacco. After drought stress treatment, the electrolyte leakage and malondialdehyde content of transgenic tobacco were lower than those of wild-type tobacco, but the proline content and soluble sugar content were higher than those of wild-type tobacco. The results of real-time PCR showed that the heterologous expression of GmGolS2-2 increased the expression of stress-related genes NtERD10C and NtAQP1 in transgenic tobacco. The above results indicated that GmGolS2-2 improved drought resistance of transgenic tobacco.

A comprehensive overview of miRNA targeting drought stress resistance in plants / Uma visão geral abrangente do miRNA visando a resistência ao estresse hídrico em plantas

MicroRNAs (miRNAs) are essential nonprotein-coding genes. In a range of organisms, miRNAs has been reported to play an essential role in regulating gene expressions at post-transcriptional level. They participate in most of the stress responsive processes in plants. Drought is an ultimate abiotic stress that affects the crop production. Therefore understanding drought stress responses are essential to improve the production of agricultural crops. Throughout evolution, plants have developed their own defense systems to cope with the adversities of environmental stresses. Among defensive mechanisms include the regulations of gene expression by miRNAs. Drought stress regulates the expression of some of the functionally conserved miRNAs in different plants. The given properties of miRNAs provide an insight to genetic alterations and enhancing drought resistance in cereal crops. The current review gives a summary to regulatory mechanisms in plants as well as miRNAs response to drought stresses in cereal crops. Some possible approaches and guidelines for the exploitation of drought stress miRNA responses to improve cereal crops are also described.

MicroRNAs (miRNAs) são genes essenciais não codificadores de proteínas. Em uma variedade de organismos, foi relatado que miRNAs desempenham papel essencial na regulação da expressão gênica em nível pós-transcricional. Eles participam da maioria dos processos responsivos ao estresse nas plantas. A seca é um estresse abiótico final que afeta a produção agrícola. Portanto, compreender as respostas ao estresse da seca é essencial para melhorar a produção de safras agrícolas. Ao longo da evolução, as plantas desenvolveram seus próprios sistemas de defesa para lidar com as adversidades do estresse ambiental. Entre os mecanismos de defesa está a regulação da expressão gênica por miRNAs. O estresse hídrico regula a expressão de alguns dos miRNAs funcionalmente conservados em diferentes plantas. As propriedades dadas dos miRNAs fornecem uma visão das alterações genéticas e aumentam a resistência à seca nas safras de cereais. A revisão atual apresenta um resumo dos mecanismos regulatórios nas plantas, bem como a resposta dos miRNAs ao estresse hídrico nas plantações de cereais. Algumas abordagens e diretrizes possíveis para a exploração das respostas do miRNA ao estresse da seca para melhorar as safras de cereais também são descritas.

Regulon: An overview of plant abiotic stress transcriptional regulatory system and role in transgenic plants / Regulon: Uma visão geral do sistema regulador da transcrição do estresse abiótico em plantas e papel nas plantas transgênica

Population growth is increasing rapidly around the world, in these consequences we need to produce more foods to full fill the demand of increased population. The world is facing global warming due to urbanizations and industrialization and in this concerns plants exposed continuously to abiotic stresses which is a major cause of crop hammering every year. Abiotic stresses consist of Drought, Salt, Heat, Cold, Oxidative and Metal toxicity which damage the crop yield continuously. Drought and salinity stress severally affected in similar manner to plant and the leading cause of reduction in crop yield. Plants respond to various stimuli under abiotic or biotic stress condition and express certain genes either structural or regulatory genes which maintain the plant integrity. The regulatory genes primarily the transcription factors that exert their activity by binding to certain cis DNA elements and consequently either up regulated or down regulate to target expression. These transcription factors are known as masters regulators because its single transcript regulate more than one gene, in this context the regulon word is fascinating more in compass of transcription factors. Progress has been made to better understand about effect of regulons (AREB/ABF, DREB, MYB, and NAC) under abiotic stresses and a number of regulons reported for stress responsive and used as a better transgenic tool of Arabidopsis and Rice.

O crescimento populacional está aumentando rapidamente em todo o mundo, e para combater suas consequências precisamos produzir mais alimentos para suprir a demanda do aumento populacional. O mundo está enfrentando o aquecimento global devido à urbanização e industrialização e, nesse caso, plantas expostas continuamente a estresses abióticos, que é uma das principais causas do martelamento das safras todos os anos. Estresses abióticos consistem em seca, sal, calor, frio, oxidação e toxicidade de metais que prejudicam o rendimento da colheita continuamente. A seca e o estresse salino são afetados de maneira diversa pela planta e são a principal causa de redução da produtividade das culturas. As plantas respondem a vários estímulos sob condições de estresse abiótico ou biótico e expressam certos genes estruturais ou regulatórios que mantêm a integridade da planta. Os genes reguladores são principalmente os fatores de transcrição que exercem sua atividade ligando-se a certos elementos cis do DNA e, consequentemente, são regulados para cima ou para baixo para a expressão alvo. Esses fatores de transcrição são conhecidos como reguladores mestres porque sua única transcrição regula mais de um gene; nesse contexto, a palavra regulon é mais fascinante no âmbito dos fatores de transcrição. Progresso foi feito para entender melhor sobre o efeito dos regulons (AREB / ABF, DREB, MYB e NAC) sob estresses abióticos e uma série de regulons relatados como responsivos ao estresse e usados como uma melhor ferramenta transgênica de Arabidopsis e Rice.

A comprehensive overview of miRNA targeting drought stress resistance in plants

Abstract MicroRNAs (miRNAs) are essential nonprotein-coding genes. In a range of organisms, miRNAs has been reported to play an essential role in regulating gene expressions at post-transcriptional level. They participate in most of the stress responsive processes in plants. Drought is an ultimate abiotic stress that affects the crop production. Therefore understanding drought stress responses are essential to improve the production of agricultural crops. Throughout evolution, plants have developed their own defense systems to cope with the adversities of environmental stresses. Among defensive mechanisms include the regulations of gene expression by miRNAs. Drought stress regulates the expression of some of the functionally conserved miRNAs in different plants. The given properties of miRNAs provide an insight to genetic alterations and enhancing drought resistance in cereal crops. The current review gives a summary to regulatory mechanisms in plants as well as miRNAs response to drought stresses in cereal crops. Some possible approaches and guidelines for the exploitation of drought stress miRNA responses to improve cereal crops are also described.

Resumo MicroRNAs (miRNAs) são genes essenciais não codificadores de proteínas. Em uma variedade de organismos, foi relatado que miRNAs desempenham papel essencial na regulação da expressão gênica em nível pós-transcricional. Eles participam da maioria dos processos responsivos ao estresse nas plantas. A seca é um estresse abiótico final que afeta a produção agrícola. Portanto, compreender as respostas ao estresse da seca é essencial para melhorar a produção de safras agrícolas. Ao longo da evolução, as plantas desenvolveram seus próprios sistemas de defesa para lidar com as adversidades do estresse ambiental. Entre os mecanismos de defesa está a regulação da expressão gênica por miRNAs. O estresse hídrico regula a expressão de alguns dos miRNAs funcionalmente conservados em diferentes plantas. As propriedades dadas dos miRNAs fornecem uma visão das alterações genéticas e aumentam a resistência à seca nas safras de cereais. A revisão atual apresenta um resumo dos mecanismos regulatórios nas plantas, bem como a resposta dos miRNAs ao estresse hídrico nas plantações de cereais. Algumas abordagens e diretrizes possíveis para a exploração das respostas do miRNA ao estresse da seca para melhorar as safras de cereais também são descritas.

Regulon: An overview of plant abiotic stress transcriptional regulatory system and role in transgenic plants

Abstract Population growth is increasing rapidly around the world, in these consequences we need to produce more foods to full fill the demand of increased population. The world is facing global warming due to urbanizations and industrialization and in this concerns plants exposed continuously to abiotic stresses which is a major cause of crop hammering every year. Abiotic stresses consist of Drought, Salt, Heat, Cold, Oxidative and Metal toxicity which damage the crop yield continuously. Drought and salinity stress severally affected in similar manner to plant and the leading cause of reduction in crop yield. Plants respond to various stimuli under abiotic or biotic stress condition and express certain genes either structural or regulatory genes which maintain the plant integrity. The regulatory genes primarily the transcription factors that exert their activity by binding to certain cis DNA elements and consequently either up regulated or down regulate to target expression. These transcription factors are known as masters regulators because its single transcript regulate more than one gene, in this context the regulon word is fascinating more in compass of transcription factors. Progress has been made to better understand about effect of regulons (AREB/ABF, DREB, MYB, and NAC) under abiotic stresses and a number of regulons reported for stress responsive and used as a better transgenic tool of Arabidopsis and Rice.

Resumo O crescimento populacional está aumentando rapidamente em todo o mundo, e para combater suas consequências precisamos produzir mais alimentos para suprir a demanda do aumento populacional. O mundo está enfrentando o aquecimento global devido à urbanização e industrialização e, nesse caso, plantas expostas continuamente a estresses abióticos, que é uma das principais causas do martelamento das safras todos os anos. Estresses abióticos consistem em seca, sal, calor, frio, oxidação e toxicidade de metais que prejudicam o rendimento da colheita continuamente. A seca e o estresse salino são afetados de maneira diversa pela planta e são a principal causa de redução da produtividade das culturas. As plantas respondem a vários estímulos sob condições de estresse abiótico ou biótico e expressam certos genes estruturais ou regulatórios que mantêm a integridade da planta. Os genes reguladores são principalmente os fatores de transcrição que exercem sua atividade ligando-se a certos elementos cis do DNA e, consequentemente, são regulados para cima ou para baixo para a expressão alvo. Esses fatores de transcrição são conhecidos como reguladores mestres porque sua única transcrição regula mais de um gene; nesse contexto, a palavra regulon é mais fascinante no âmbito dos fatores de transcrição. Progresso foi feito para entender melhor sobre o efeito dos regulons (AREB / ABF, DREB, MYB e NAC) sob estresses abióticos e uma série de regulons relatados como responsivos ao estresse e usados como uma melhor ferramenta transgênica de Arabidopsis e Rice.

The pattern of alternative splicing and DNA methylation alteration and their interaction in linseed (Linum usitatissimum L) response to repeated drought stresses

BACKGROUND: Drought stress has significantly hampered agricultural productivity worldwide and can also result in modifications to DNA methylation levels. However, the dynamics of DNA methylation and its association with the changes in gene transcription and alternative splicing (AS) under drought stress are unknown in linseed, which is frequently cultivated in arid and semiarid regions. RESULTS: We analysed AS events and DNA methylation patterns in drought-tolerant (Z141) and drought-sensitive (NY-17) linseed under drought stress (DS) and repeated drought stress (RD) treatments. We found that the number of intron-retention (IR) and alternative 3' splice site (Alt3'SS) events were significantly higher in Z141 and NY-17 under drought stress. We found that the linseed response to the DS treatment was mainly regulated by transcription, while the response to the RD treatment was coregulated by transcription and AS. Whole genome-wide DNA methylation analysis revealed that drought stress caused an increase in the overall methylation level of linseed. Although we did not observe any correlation between differentially methylated genes (DMGs) and differentially spliced genes (DSGs) in this study, we found that the DSGs whose gene body region was hypermethylated in Z141 and hypomethylated in NY-17 were enriched in abiotic stress response Gene Ontology (GO) terms. This finding implies that gene body methylation plays an important role in AS regulation in some specific genes. CONCLUSION: Our study is the first comprehensive genome-wide analysis of the relationship between linseed methylation changes and AS under drought and repeated drought stress. Our study revealed different interaction patterns between differentially expressed genes (DEGs) and DSGs under DS and RD treatments and differences between methylation and AS regulation in drought-tolerant and drought-sensitive linseed varieties. The findings will probably be of interest in the future. Our results provide interesting insights into the association between gene expression, AS, and DNA methylation in linseed under drought stress. Differences in these associations may account for the differences in linseed drought tolerance.

Eco-physiological behavior of tamarind (Tamarindus indica L.) in dry environment of West Africa (case study of Senegal).

Water deficit is considered by several authors to be the most limiting factor for agricultural production in the subtropics (Kizito et al., 2006; Porcel and Ruiz-Lozano, 2004; Bader et al., 2006; Logan et al., 2010; Rodriguez-Gamir et al., 2011; Conedera et al., 2011). On woody plants, only a few isolated studies (on Acacia, and combretaceae) exist in the tropical zone south of the Sahara. Noteworthy are the works done on Sahelian forest species, Acacia tortilis (Diouf, 1996), Combretum glutinosum, Guiera senegalensis; Piliostigma reticulatum; Balanites aegyptica, Boscia senegalensis, A. senegal and Ziziphus mauritiana (Fournier, 1995; Kizito et al., 2006; Lufafa et al., 2008). Characterization of plant water functioning is a tool for selecting plants and/or varieties for their tolerance to water deficit (Lufafa et al., 2008; Zhu Qiuan et al., 2011; Logan et al., 2010). It is most often done at young age for ease of use (nursery and early field establishment of seedlings). However, even as adults, woody plants remain dependent on climatic factors such as rainfall (Kisito et al., 2007; Lufafa et al., 2008). It is therefore important to understand the in situ water functioning of adult plants to better explain the depressive effects of such complex water stress at a young age. However, the behavior of plants in situ is influenced by the climatic conditions and the uniformity (age) of the subjects (tamarind plants) to be followed. The present work was carried out on adult T. indica plants in situ in Senegal (Niokhoul in the Sahelian zone and Mbassis in the Sudano-Sahelian zone) and aimed mainly to: (1) understand and describe the physiological water management strategies of tamarind under arid conditions; and (2) understand the impact of this water management strategy on phenology and productivity. The study was conducted in Senegal, characterized by a dry and arid climate. It adopted a field approach (Seghieri, 2010; Conedera et al., 2010) based on adult stands and climatic data collected at the study sites. Ultimately, the adaptation mechanism of tamarind to water deficit would be that of avoidance, described by various authors (Khalfaoui, 1985; Lacape, 1996; Nwalozie and Annerose, 1996; Rouhi et al., 2007; Roussel, 2008; Maes et al., 2009). Indeed, the plant first proceeds to a decrease in water potential (case of the Mbassis stand) and in case of continuous water deficit, it integrates the reduction of the leaf surface by the progressive fall of the leaves and flowers which can go up to the total defoliation (case of the stand of the Sahelian zone in Niokhoul).

Validating the physiological potential of zero monopodial compact cotton TCH 1819 culture by chemical manipulation

Cotton is the most important global cash crop which controls economy of many nations. Global sustainability of cotton yield is one of the major challenges for meeting impending threats under climate change. Though India is one among the leading countries in cotton production, the supply is not enough considering the increasing demand. Scientists across the Globe are indulged in developing new lines and cultures with capacity to produce more yields. In this context, here, we have made an attempt to study the growth, physiology, and yield traits of cotton culture - TCH 1819 before its release (now released in the name of CO 17) by different chemical treatments. Observation on the leaf gas exchange traits, leaf parenchymal cells distinguished the source sink relationship of the culture. Chemical manipulation by growth retardants reduced the gibberellins content and modified the foliage structure. By characterizing the physiological potential through manipulation by growth retardant (Mepiquat chloride (0.015 %)) increased the yield by 30%. The traits identified in this study are potential indicators in breeding programme before releasing the variety.

EXPLORING THE SOLASTALGIA: PREDICTING THE COGNITIVE FAILURES AMONG DROUGHT PRONE FARMERS

The climatic changes mainly effect the farming profession as, India is regarded as an agricultural portion of the globe because many of its regions are perfect for agrarian production; Due to this shift in climate various types of natural disasters are taking place. One such calamity among several disasters is drought. The present paper focuses on the cognitive failures experienced by the farmers suffering with drought. This paper attempts to study the psychological turmoil experienced by the famers which is termed as, Solastalgia. It is a novel concept that has evolved to make environmental distress more meaningful and clearer. Unlike nostalgia — the morose or anxiousness encountered by individuals who get separated from their home — Solastalgia is the havoc caused by changes in the environment, as it affects people while they are attached to their home settings. The results manifested that the grief observed among the farmers due to the change in their environment hits the mental health and psycho- social status of the agriculturalists. The most important indicator for intellectual failures in the pandemic circumstances is constant substance abuse done by the farmers due to the crop failures they have experienced

Effect of type of mature embryo explants and acetosyringone on agrobacterium-mediated transformation of moroccan durum wheat

Drought is one of the major constraints in durum wheat production in the Mediterranean Basin. In order to overcome this problem, the genetic transformation of durum wheat is one of the choices for improvement. However, the recalcitrance to Agrobacterium-mediated transformation in durum wheat (Triticum turgidum L.) is one of the factors limiting a successful genetic transformation. The aim of this study was to investigate the effect of explant type and acetosyringone concentration for the efficient Agrobacterium-mediated genetic transformation of three Moroccan durum wheat varieties (Amria, Chaoui, and Marouane). The mature embryos (intact, halved and pieces) were inoculated with Agrobacterium tumefaciens strain EHA101 harboring the binary vector pTF101.1 containing drought tolerance gene HVA1 from barley, and a selectable marker phosphinothricin (PPT) resistance (bar) gene. The explants were inoculated with A. tumefaciens (cell density OD650 at 0.7) at four different concentrations of acetosyringone (0, 100, 200, and 400 µM). The results showed that embryogenic calli from mature embryos showed higher regeneration and transformation than mature embryo halves and pieces. The integration of the transgene was confirmed by PCR amplification using primers specific to the bar gene, 2x35S promoter, and HVA1 gene. The transformation efficiency ranging from 0.33% to 2.33% was obtained in Amira variety using embryogenic calli and acetosyringone concentrations of 200 and 400 µM. The integration, as well as inheritance of the transgene, was confirmed by PCR amplification in T0 and T1 generations. This is the first report describing a genetic transformation of Moroccan durum wheat varieties via Agrobacterium tumefaciens.